DIY Doctor UK DIY Forums

Forgive me if someone has already asked this question - I cannot find it if they have.
I have a 7-year old condensing system with a Potterton boiler (already replaced the PCB). There is a water storage tank in the airing cupboard and this buzzes. On the front of the storage tank there are 2 dials, one is the timer and the other has a summer and winter setting to optimise efficiency. The buzzing noise comes from behind the front panel where these dials are.
It occurs at regular intervals throughout the day and night and irrespective of whether the boiler and heating system is on or off. The only way to stop it is to switch off the power to the tank.
Any ideas.

Immersion heater ? as with alot of electrical equipment the noise gets louder the older they get.

You could replace it - or get an engineer out to make sure that's the fault.

What if you turn the boiler off ? is the water always hot ? I'm guessing the immersion is on to keep the water at a set temperature - therfore will come on at different times.

Thanks. I'm not aware of ever having used the immersion heater, but the water is always hot - i was told that it is heated on demand. If the boiler is off, the water is cold.
I have turned down the temperature dial on the actual boiler which has reduced the occurance of the noise greatly, but not got rid of it completely. The dial was set to MAX which is how the plumber who fitted our PCB left it.